Looper mechanism for sewing-machines.



J. R. MOFFATT. LOOPERY MECHANISM FOR SEWING MACHINES. APPLICATION HL'ED MAR. 9, 1914.

1,21 7,980 v Patented Mar. 6, 1917.

1. R. MOFFATT. I LOOPER MECHANISM FOR SEWING MACHINES.

APPLICATION FILED MAR. 9, 19M. 7

Patented Mar. 6, 1917.

2 SHEETS-SHEET 2- wrmm h 1 n m rran stares PATENT @FMQE A JAMESR. MOFFATT, or CHICAGO, ILLrNoIs, AssIeNoR T0 UNION SPECIAL MACHINE COMPANY, or ciiIcAeo, :tTLLIivoIs, A CORPORATION or ILLINOIS.

LOOPER MECHANISM FOR SEWING-MACHINES.

. Application filed March 9; 1914. Serial No. 823,402.

To all whom it may concern:

Be it known that I, JAMESR. Mar am, a citizen of the United States, residing at Chicago, in the county of Cook, State of Illinois, have inVented'certain new and useful Improvements in Looper Mechanisms for Sewing-Machines, of which the following-is a description, reference being had to the accompanying drawing and to the figures of reference marked thereon. j

The invention relates to new and useful improvements in looper mechanisms fer sewing machines and more particularly to a looper mechanism wherein the looper is a thread carrying looper and 'has' a lateral needle avoiding movement, as well as V a movement into and out ofthe'iieedle loop;

. 'An object of the invention is to provide a means for vibrating the looper laterally, which may bereadily adjusted for varying the lateral throw of the looper, which means consists of few parts, is of simple construc-' tion, and may be readily applied to the operating shaft of a sewing machine.

In the drawings which show by way of illustration one embodiment of the invention, v

Figure 1 is a front view. of a part of a sewing machine having my improved l'oop'er mechanism applied thereto.

Fig. 2 is a plan view ofthe' s'aine.

Fig. 3 is a detail, showing in side elevation the mechanism for operating the looper laterally.

Fig. 4 is a a and the means for supporting'the sameiin longitudinal section. 1

Fig. 5 is a detail, showing the main shaft in transversesectioii and the supporting sleeve and flange for the eccentric in face view. 7 Y l Fig, 6 is a plan view of the flanges carried by the eccentric and the sleeve, showing the interlocking tongue and recess ,and ad justing screw. I I

Fig; 7 is an end view of the eccentric, showing the flange in face view.

Fig.8 is an end view of the sleeve, showing the inner face of the'fiange carried thereby.

Fig. 9 is a diagrammatic View, showing the path of travel of the looper in two of its adjusted positions.

The invention consists generally in providing a mechanism for oscillating the looper i Specification of Letters Patent.

tail, showing the eccentric Patented Mar. 6, 1917.

laterally, which consists of a supporting sleeve on the operating shaft and an eccentric which surroundsthis sleeve, the opening through the eccentric beinglarger than the sleeve so that said eccentric may be adjusted laterally. The eccentric is attached to the sleeve and held injvarious adjusted positions thereon by locking bolts. The eccentric is moved laterally on the sleeve by an adjusting screw arm in which-is mounted a needle bar 8, carrying, as herein shown, three needles, indicated at 1. j j

A' looper 5 coeperates with all three needles and is so disposed as to swing about a pivotal axis substantially at right angles to a plane containing the three needles. The looper is mounted on a carrier 6 which is pivoted at 7 to a looper support 8. This looper support is in turn pivoted in the brackets 9 and 10 carried by the bed 1. The looper carrier 6 is oscillated on its pivotal support 7 by a link 11, whichis pivotally connected to the needle lever extension 12 of the well known construction. p

The looper support 8 is vibrated so as to give the looper 5 a lateral or needle avoiding movement by an arm 13, which is carried by a collar 14 secured by a set-screw 15 to the looper support. The arm 13 is in the form ota ball and is connected directly to an eccentric strap 16, which coeperates with an eccentric 17 on the main shaft 18.

As clearly shown in Figs. 1 and 5, the'ec-' centric 17 is supported bya sleeve 19. This sleeve '19 fits on the shaft 18 and is held thereon by'a spot-screw 20. The sleeve 19 has an integral flange 21. The eccentric 17 is formed alsojwith an'integr'a'l flange 22. These flanges are milled so as to fiti snugly together. One of the flanges is formed-withan extended tongue 23 which fits in recess 24 in the other flange; Between these flanges is an opening 25, one half ofwhieh is formed in one of the, flanges and the other half in the other flange. The half formed in the flange carried by the eccentric is threaded, while the other half is a The screw 26 is formed with a head 28 which engages this cross-slot or recess 27. The flange 22, as above noted, has its section forming the opening between the flanges threaded and the lower end of this part of the opening 25 terminatesin a recess which receives the head 28 of the screw 26 (see'Fig. i) and said recess at its inner end is cut away as at 27 so as to permit the head of the screw to pass through (see Fig. 8). The opening 29 in the eccentric l"? is considerably larger in diameter than the external diameter of the sleeve 19. The outer end of the screw 26 is slotted to receivev the usual ments to the looper.

operating tool. When the screw is rotated, it will rotate in the section of the opening formed in the flange 21 without any movement endwise therein, as this section of the opening is without threads and the head 28 of the screw fits in the recess 27 which prevents any endwise movement thereof. This turning of the screw, however, which has threaded engagement with the flange 22, will bodily move the flange 22 radially of the sleeve 19 and the recess 2. permits this adjustment of the eccentric on the sleeve. hen the head 28 of the screw 20 engages the top of the recess 27 in the flange 22, the eccentric has reached its extreme lateral adjustment in this direction, as shown in Fig. 4;. This screw is not shown in Fig. 8, but only the screw threaded recess for it.

The flange 21 carried by the sleeve 19 is formed with parallel slots 30 and. 31. The threaded bolts 32 and 33 engage respectively these slots and these bolts are threaded into the flange 22 carried by the eccentric. When it is desired to adjust the eccentric these threaded bolts are loosened and by turning the screw 26 the desired adjustment may be secured, after which the bolts are turned up so as to clamp the parts in this adjusted position.

It will be apparent from the above de scription that I have provided means for mounting and adjusting the eccentric which is extremely simple and efficient. The sleeve may be slipped onto the operating shaft of the sewing machine and the spot screw 20 turned in order to fasten the sleeve in position. 2 The eccentric is formed with a suitable opening to permit the manipulation of this spot screw. (See Fig. 3). The eccentric strap 16 will be oscillated by the eccentric and this will impart the lateral n1ove- VVhen it is desired to adjust the throw of the looper, the locking bolts are released and the eccentric turned to a position wherein the screw 26 is accessible and upon turning this screw the parts will be shifted so as to position the eccentric for giving a different throw to the looper.

In Fig. 9, I have showndiagrammatically the path of movement of the looper. The flattened ellipse indicates at a, .b, 0, (Z one path of movement of the looper, while the flattened ellipse a, e, 0, f indicates another path of travel of the looper.

My improved looper mechanism is especially adapted for a sewing machine having a plurality of needles, as indicated in the drawings. In a machine of this character with a single looper, it is essential that the looper shall travel in a substantially straight path as it enters the needle loops, so that the looper may be moved close to the needles and avoid any possible skipping of the needle loops, Inasmuch as the needles are necessarily spaced, the distance in which the looper must move in substantially a straight line is considerably prolonged. It will be apparent, however, from the diagrammatic figure showing the path of travel of the looper that I have provided a looper mechanism wherein this desired movement of the looper is secured. When the needles are changed and larger needles are used, it is essential that the path oftravel of the looper should be also shifted to accommodate the different sized needles. That is, if the needles are larger than before, the looper point must be moved over as to its path of travel, so as not to strike the needles but pass close to each needle. On the other hand, if the needles are smaller than before, the shift must be in the other'direction to bring the looper point up close to the smaller needles. This adjustment can be readily secured, as indicated in Fig. 9, which figure shows the extreme adjustment which may be accomplished by shifting the eccentric.

It is obvious that minor changes in the detail of construction and arrangement of parts may be made without departing from the spirit of the invention as set forth in the appended claims.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A sewing machine including in combination, a shaft, a sleeve fixed to said shaft and having a flange projecting outwardly therefrom, an eccentric surrounding said sleeve and having an opening larger than said sleeve, a flange carried by said eccentric, an opening conj ointly formed in said flanges, the section of the opening in the flange on the sleeve being threaded and in the other flange being smooth, a screw located in said opening and having its thread engaging the threaded section thereof, the smooth section of the opening terminating in a recess extending transversely thereof, said screw having a head thereon engaging said recess whereby said eccentric will be shifted radially relative to' the axis of the shaft upon manipulation of the screw.

2. A looper mechanism for sewing machines, comprising a looper, means for oscillating the looper into and out of the needlethread loop, a shaft, and means for moving the looper laterally including a sleeve fixed to said shaft, said sleeve having a flange projecting outwardly therefrom, an eccentric, a flange carried by said eccentric and engaging the flange on the sleeve, means for looking said flanges together, an opening formed between the flanges, the sections of the opening in one of said flanges being threaded and in the other flange being smooth, a screw 10- cated in said opening and having its thread engaging the threaded flange section, the sec: tion of the opening in the flange which is smooth terminating in a recess extending transversely thereof, said screw having a 1) head thereon engaging said recess, whereby said screw is held from endwise movement on said flange having said smooth section of the opening.

In testimony whereof, I aflix my signa- 25 Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

